1. Field of the Invention
This invention relates to a controller of a movable member which moves the member between two states using one electromagnet, for example in a tape recorder.
2. Discussion of the Background;
Conventionally, the movable member was moved from the first position to the second position by combining the movable member, which moves freely between the first and the second positions, with the driving part. Also the controller for the movable member which stays in its second position is well-known.
In this conventional controller for the movable member, an electromagnet has been used for combining the movable member and the driving member and another electromagnet used to hold the movable member in the second position. In such a two electromagnet system, an electric current switching circuit for selecting the flow into the two electromagnets was needed to control the increase of current capacity and heat generating quantity. As a result, there is a problem in trying to reduce the size and weight due to its complex constitution and the necessity of wider space for those installations.
In order to solve this problem, an electromagnet having two attracting parts was used. This electromagnet can perform both functions of combining the movable member with the driving member and holding the movable member in the second position.
However, when combining the two functions in one electromagnet, since the attracting force is weakened when the attracted part has been attracted at the same time by the two attracting parts of the electromagnet, the capacity of the electromagnet must be increased. Thus there is a problem which requires a higher electric power consumption as well as a higher price.